Field of the Invention
The invention is related to an adjusting mechanism, and more particularly, to a lens adjusting mechanism.
Description of Related Art
The projector is a display device for generating a large screen. According to an imaging principle of the projector, a lighting beam generated by a light source module is converted into an image beam by a light valve. Afterwards, an image is formed when the image beam passes through a lens and is projected unto a screen or wall. With recent advancement in projection techniques and reduced manufacturing cost of the projector, applications of the projector have been gradually expanded from commercial use to household use.
In general, an optical element such as a lens is between the light source module and the light valve in the projector to transmit the lighting beam generated by the light source module to the light valve. Since manufacture and assembly tolerances cause light beam offset such that light beam cannot fully cover the light valve, the overfill ratio of the light beam needs to be increased by an optical design to fully cover the light valve. However, increasing the overfill ratio of light beam results in loss of brightness such that the efficiency of the light source cannot be optimized.